All nature names and Celeste is the best. Tallulah, though a valid name, sounds like someone who just came out of hiding in the back hills. Aqua sounds as though you were expecting a mermaid. Celeste is simply lovely. Middle name ideas:
Celeste Aurora (still a nature name)
Celeste Rae (Rae means "doe")
Celeste Brooke
Celeste Mariah